c.1460, "to settle," from O.Fr. resider, from L. residere "to remain behind, rest," from re- "back, again" + sedere "to sit" (see sedentary). Meaning "to dwell permanently" first attested 1578. Resident first recorded 1382, as an adj.; the noun meaning "one who resides"
is from 1487. Meaning "medical graduate in practice in a hospital as training" first attested 1892, Amer.Eng.